• Animal cells and systems
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• v.9 no.3
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• pp.139-144
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• 2005

The attractant (orange light) or repellent (white light) signal is transmitted from SRI (Sensory Rhodopsin I) via protein-protein interaction with its transducer Htrl (Halobacterial Transducer for Sensory Rhodopsin I) which in turn controls a cytoplasmic phospho-transfer pathway that modulates flagella motor switching in Halobacterium salinarum. Some mutations in both SRI and Htrl showed an unusual mutant phenotype called inverted signaling, in which the cell produces a repellent response to normally attractant light. Twelve mutations at the Glutamate 56 (E56) position in the second transmembrane helix of Htrl were introduced by site-specific random mutagenesis. Almost all E56 mutants showed orange-light inverted responses in pH and temperature-dependent manners except E56D and E56Y. Except for these two mutants, all mutants accelerated the $S_{373}$ decay compared to wild-type at $18^{\circ}C$. This supported that there is an interaction between SRI and the second transmembrane of Htrl. Also a structural model of Htrl based on the Tar crystal structure and the secondary structure prediction program proposed the E56 residue to be in the middle of the proton channel. The most important observation is that the E56 mutant provides the evidence that this residue is very sensitive for signal relay, which can be explained by the open and closed conformations of the channel (A and R conformations) in SRI, as was postulated by the unified conformational shuttling model for transport and signaling.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.6
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• pp.1795-1799
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• 2008

The heterogeneous nuclear ribonucleoprotein K (hnRNP K) is a component of hnRNP complexes. This protein binds strongly to cytidine-rich RNA/DNA sequences. It is a nucleocytoplasmic shuttling protein. To investigate the functions of hnRNP K, I searched for hnRNP K-interacting proteins in HeLa cDNA library using a yeast two-hybrid screening system. One of the cDNA clones is identical to human hnRNP E1 (poly(rC) binding protein 1) cDNA (GenBank accession number XM_031585). In this study, hnRNP K is shown to specifically interact with hnRNP E1 in yeast two-hybrid system and in vitro biochemical assay.

• Journal of KIISE
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• v.42 no.7
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• pp.840-845
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• 2015

In recent years, Big Data has been a topic of great interest for the production and operation work of offshore plants as well as for enterprise resource planning. The ability to predict future equipment performance based on historical results can be useful to shuttling assets to more productive areas. Specifically, a centrifugal compressor is one of the major piece of equipment in offshore plants. This machinery is very dangerous because it can explode due to failure, so it is necessary to monitor its performance in real time. In this paper, we present stream data processing architecture that can be used to compute the performance of the centrifugal compressor. Our system consists of two major components: a virtual tag stream generator and a real-time data stream manager. In order to provide scalability for our system, we exploit a parallel programming approach to use multi-core CPUs to process the massive amount of stream data. In addition, we provide experimental evidence that demonstrates improvements in the stream data processing for the centrifugal compressor.

• Applied Chemistry for Engineering
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• v.32 no.4
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• pp.467-471
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• 2021

A ladder-like polysilsesquioxane (LPMA64) functionalized with a crosslinkable group was synthesized and used for the preparation of organic-inorganic hybrid gel polymer electrolytes through a thermal crosslinking process of the liquid electrolytes. A small weight percent of LPMA64 polymer crosslinker (5 wt%) was able to form a well-developed network structure, resulting in good dimensional stability with high ionic conductivity. The lithium-sulfur batteries fabricated with organic-inorganic hybrid gel polymer electrolytes exhibited stable C-rate and cycling performance with excellent Coulombic efficiency due to the alleviated lithium polysulfide shuttling effect during prolonged cycling. The result demonstrates that the organic-inorganic hybrid gel polymer electrolytes could be a promising candidate electrolyte for application in lithium-sulfur batteries.

• Journal of Ginseng Research
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• v.47 no.2
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• pp.311-318
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• 2023

Background: The beneficial effects of compound K (CK) on different chronic diseases have been shown to be at least related to antioxidant action. Nevertheless, since its antioxidant activity in human retinal pigment epithelial (RPE) cells is still unknown, here we investigated whether CK alleviates oxidative stress-stimulated damage in RPE ARPE-19 cells. Methods: The cytoprotective consequence of CK in hydrogen peroxide (H₂O₂)-treated cells was evaluated by cell viability, DNA damage, and apoptosis assays. Fluorescence analysis and immunoblotting were performed to investigate the inhibitory action of CK on reactive oxygen species (ROS) production and mitochondrial dysfunction. Results: H₂O₂-promoted cytotoxicity, oxidative stress, DNA damage, mitochondrial impairment, and apoptosis were significantly attenuated by CK in ARPE-19 cells. Furthermore, nuclear factor erythroid 2-related factor 2 (Nrf2) phosphorylation level and its shuttling to the nucleus were increased, which was correlated with upregulated activation of heme oxygenase-1 (HO-1). However, zinc protoporphyrin, a blocker of HO-1, significantly abrogated the preventive action of CK in H₂O₂-treated ARPE-19 cells. Conclusion: This study indicates that activation of Nrf2/HO-1 signaling by CK plays an important role in rescuing ARPE-19 cells from oxidative cellular damage.